Editor’s Note: What’s true of Viagra and other pharmaceutials is also true of cigarettes, counterfeits kill and the black market in them is widespread. Moreover, as described below, the same toxins that contaminate the fake pharmaceuticals are the same ones found in counterfeit cigarettes, elevated levels of heavy metal and shop sweepings.

In the past year, evidence has mounted that a large percentage of the Viagra and other erectile dysfunction (ED) medication sold online is fake. And that the majority of the sites selling Viagra online can’t be trusted.

It started with data presented at the World Meeting on Sexual Medicine late last year showing that 77 percent of all Viagra (generic name sildenafil) purchased online from 22 different sites was counterfeit. (Note: The study was published only as an abstract for presentation at the conference and therefore has to be considered preliminary. And the author, Irwin Goldstein, M.D., conducted the study in cooperation with the global security arm of Pfizer, maker of Viagra.)

But since then, one revelation after another has added to the momentum, suggesting that the majority of sites selling Viagra and other drugs online are untrustworthy and likely trafficking in counterfeit meds, and that fake Viagra is being smuggled into the country in alarming quantities.

The Majority of Online Pharmacies Untrustworthy, Officials Say

Last month, the National Association of Boards of Pharmacy (NABP), which accredits online pharmacies, announced the results of an analysis showing that 97 percent of the more 10,000 online sites selling prescription medications were operating illegally or not following pharmacy laws and standards. (Note: This is prescription medications; the report did not even touch the websites selling drugs without a prescription.)

And in June the FDA announced results of a sting titled Operation Pangea IV that busted 1677 online pharmacies for selling counterfeit medications. The agency seized website domain names and posted messages on the sites to alert potential consumers that buying and selling counterfeit drug is illegal and can result in severe penalties.

Large Quantities of Fake Viagra Seized This Summer

This summer also saw the FDA and customs officials cracking down on smugglers and distributors of fake ED drugs. Last week a man caught bringing fake Viagra into Los Angeles International Airport was convicted and sentenced to two and a half years in prison. In August, two men were indicted in Texas for smuggling counterfeit Viagra, coming on the heels of a similar indictment of a Pensacola, Florida man for trafficking and sales of Viagra and other ED drugs.

In January, 2013 customs officials intercepted 180,000 counterfeit Viagra pills at Miami International Airport. And these are just a handful of the cases currently in courts. The most recent Federal data show that seizures of counterfeit drugs are up by 200 percent and fake medications are now number six on the list of most-seized items.

In February of this year, the Institute of Medicine (IOM) issued a scary report on the worldwide counterfeit drug trade and called on the U.S. to institute a “track and trace” system to keep track of drugs from manufacture to purchase.

Data on Fake Viagra May Be Exaggerated

The belief that most online pharmacies are suspect and that most Viagra sold online is fake is not universal, however. In fact, says Roger Bate, a scholar at the American Enterprise Institute and author of Phake: The Deadly World of Falsified and Substandard Medicines, his own tests of drugs sold online found the vast majority to be authentic and those sold by credentialed online pharmacies to be 100 percent authentic. Bate published a paper in 2010 finding that just 7.3 percent of Viagra samples purchased online failed spectrometry testing and proved to be fake.

Taking Fake Viagra Can Have Life-Threatening Consequences

Experts may argue about how much of the Viagra sold online is counterfeit, but there’s little disagreement about the significant dangers posed by taking fake Viagra and the fact that those purchasing it seem blissfully unaware of the risks they’re taking.

Ticking off a list of known dangers, Bates cites potential toxicity from heavy metals and other unknown ingredients, and the risk of fungal and bacterial infection from drugs manufactured in unsanitary conditions. “No one would go licking the garage floor, but that’s basically what you’re doing when you buy counterfeit drugs,” Bate says.

Here are a few of the ingredients found in confiscated counterfeit Viagra:

Blue printer ink

Speed or amphetamine

The antibiotic Metronidazole (Flagyl)

Drywall and plaster

Other ingredients and dyesused to mimic the texture and color of real Viagra

Then there’s the even more serious risks raised by the unregulated dosages in counterfeit Viagra. Most men, Bate says, assume that the worst that could happen with fake Viagra is that it simply won’t work. But the opposite may be just as true, and much more dangerous – the drug can be super potent, with the potential to trigger a heart attack. Given that men with erectile dysfunction are already at increased risk for cardiovascular disease (which can cause ED), this is a very real danger.

Pfizer Fights Back

In a dramatic counter-maneuver, this summer Pfizer itself began selling Viagra online through the company’s own website. As reported by the New York Times, experts say Pfizer could be losing hundreds of millions of dollars a year in potential sales of Viagra, a blockbuster drug with sales of more than $2 billion in 2012.

The Problem is Only Going to Grow

There are numerous reasons why counterfeit ED drugs have become such a huge industry, says Roger Bate, but the the primary one is obvious. “Men will pay almost anything if they suffer from erectile dysfunction, and many are too embarrassed to tell a doctor and get a prescription.”

Then there’s the fact that counterfeit Viagra is a smuggler’s dream product, Bate says. “The market is huge, the chance of being caught is low and the penalties are very trivial.” Which is exactly what makes it so scary. “Viagra can function like a gateway drug for smugglers,” Bate says. “They realize they can make a lot of money, then next they start faking antibiotics and cancer drugs and other medications where it makes a life or death difference if they work or not.”

So You Want to Buy Viagra Safely Online. What to Do?

There are a number of resources specifically created to enable consumers to shop safely online. The National Association of Boards of Pharmacy (NABP) offers its own website to find an accredited online pharmacy, AwareRX, which lists pharmacies vetted by the NABP through their VIPPS program (Verified Internet Pharmacy Practice Sites). The FDA also has its own consumer protection website campaign launched in late 2012, BeSafeRX.

Bate offers the advice to use only credentialed online pharmacies, acknowledging that these pharmacies require valid prescriptions.

Have you had experience with counterfeit drugs? Please share in the comment section below. And if you think a drug you’ve purchased is fake, report it to the FDA’s Medwatch program (800-332-1088) or your state pharmacy board.